I think a KUL ES-87 with Clears will suit you very well. Clears are great for both typing and gaming. They're the most tactile MX switch. The bump can be used as a reference for where the actuation point is, which helps for rapid double-taps or "hovering" for FPS gaming.
About stabilisers: Cherry stabs can be clipped to take away the "mushy" bottom out. This is not an issue if you use orings, though, since they act at a similar point. They're better for changing keycaps, less susceptible to rattle and don't have clearance issues with thick caps like Costar style do.
KHAANNN's comment about "loose" Signature Plastics caps... No idea where that comes from since all my SP caps are tight on the stems. Also, cutting inserts? WTF? All caps work with Cherry stabs with no mods needed, full stop.
About orings: Keycaps do not touch the casings on bottom out. Bottom out happens when the slider hits the bottom casing (in the case of the clicky switches it's the pin that hits, in the case of tactile and linear it's the wider part of the slider). Orings need to be chosen dependent on the keycap profile and personal taste. The keycap profile will determine how much space there is between the bottom of the cap and the top of the switch case at the bottom out point. THIS IS DIFFERENT FOR DIFFERENT PROFILES, and even "OEM" profile can have a few different gaps since they're made by different manufacturers. Some profiles (like sculptured SA) even have different distances from one row to another which requires different orings per row to maintain a consistent feel. Most orings used for keyboards are made of very durable materials which will last for many years, you shouldn't be concerned about longevity, except for really long term (10 years or more I'd guess).
Orings are meant to soften out the shock of bottoming out hard plastic to hard plastic. They do not change the bottom out force, except by possibly reducing the travel very slightly and thus bottoming out at a slightly higher point in the spring compression, but this is negligable. Of course, if you really try to hit hard plastic by compressing the oring to this point, you could argue that that's a massive increase in force, but you should instead consider the point of oring contact to be "bottoming out". With some orings it's not even possible to make the plastic make contact.
Landing pads are a softer material than orings and usually a bit thicker. They give a more progressive "soft landing" which feels a little different to orings.
If you're adventurous, you can attempt the "trampoline mod". This involves inserting a piece of soft material into the tube inside the switch to act against the slider pin when approaching bottom out. You can tailor the mod for different feel and travel reduction by changing the shape and material used. IMSTO sells some nice little silicone balls which work well for this and give a consistent feel, quite similar to orings. The biggest advantage of this mod is that it works consistently with any keycap.
About ping: Ping can be cured easily enough and doesn't bother most people. It's most prevalent on strong spring clicky switches with no orings or other damping method, least on light spring linears with orings. Usually it's caused by a spring resonating, due to either the click mechanism, bottoming out or the spring twisting when compressed, catching and then releasing at either the bottom casing or slider end. Lubing prevents this "catching" and can dampen the resonance, too, effectively silencing the spring.
Plate resonance is not the same as ping, but is often mistaken for it. This can be cured by a few methods, inclusing adding drawer liner as a damping material or rubber pieces to the plate to dampen the resonance. It can cause spring resonance, though, so it may be hard to diagnose which you have, or what measure of both.
